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110X2005 14:13 FRfiNCISCO JfiYPLfi* 94053257490 NO.055 30 The Providence Journal, Friday, April 28, 1967 >MWIill!ii:<i1J!lilini|||!M illlllllilw^^ BOOKS IN REVIEW 'There Will Be None Forever ' INTELLIGENT LIFE IN THE UNIVERSE, bv I, S. Sltklnvskii and Cnrl Sa^nn. 50f) pagea. Holdcn-Day, 98,95. By FRANCISCO J, AVALA Aror there other intelligent beings in the universe? Is the immense universe that mod- ern astronomy has discovered (illod with civilizations simi- lar perhaps In certain ways to our own? Or can St bo that the hiarl.h Is unique, and that WR are forever alone In the 'Intelligent Life In tlie Uni- verse1 is the product of a unique international collabo- ration between a world fam- ous Russian astronomer and R brilliant. space sricn- j list From Harvard Univer- sity. Shk.1av.sUii and Sagnn had never mnt previous In publication. Their coopera- tion has produced an inform- ative and well written book, full of excitement. It Is ad- dressed to the general pviblic at large, not only to the space scientKsts. Without sac- rifice of accuracy they have succeeded $n producing a highly readable work, in spite of its five hundred pages and the intricate .nature oC the subject, The. book Is divided Into three parts. Tlie first part deals with, the 'origins and evolution of the universe, the second and third parts with the existence of life, and of intelligent life In other plan- ets. respectively, Whether an astronomer be- llovea the Immensa space of our ffalaxy to be -populated by planets depends on what theory he accepts to explain the origin of planets. It is the authors' contention that a considerable percentage of stars are accompanied by planets, if ten per cent of the stars of the Galaxy are circled by planetary systems similar to our own we reach the remarkable conclusion that there arc-some 15 billion planetary systems in our gal- axy alone. The physical conditions need- ed in a planet for life to exist are very stringent indeed. In the -solar•'•system • only Mars has -a. slight probability of harboring sprno. primitive focms of life: similar to those on earth.' •ScirnHsts, however, have'speculated that different forms , of ik*lr*i*pp1icating or- panisms may p>:ist, Living or- canisins which rhrivn without oxygon exist in our planet. Life based on the clement sil- icon rather than carbon could have developed in other plnn- ets. Shklovskii and Sagan con- clude that fit least a billion stars In our Galaxy may have habitable planets: But what about rnan? What about the evolution of Intelli- gence? Is it reasonable to as- sume that a large number of planets are inhabited by or- ganisms with intelligence and manipulative abilities more or less similar to our own? It Is at tbis point that the authors make the most remarkable, and I must add-, most unac- ceptable assumption. In their opinion the fraction of planets having life in vvhich intelligent beings are expected to arise by evolution is at least of one out of ten. Taking Into con* si deration other limiting fac- tors they, es-timate that there are at present about one mil- lion advanced technical civili- zations in the galaxy. I wish 1 could go along with the authors' optimism. As- tronomers in general agree that planets probably exist In large numbers. The fact re- mains, however, that there is no direct evidence of the ex- istence of a single planet our- side the solar system, Virtual- ly all biochemists agree that life arose spontaneously from nonliving matter. If there are many Karth-like planets, it is reasonable to speculate that life has arisen repeatedly In the universe, evm though we do not know whether that is a fact, Life arose on Earth some three billion years aso, On the j; geological time scale man is j a newcomer. Man came into existence in 1hc last, two mil- lion yogi's. Organic evolution || is an opportunistic process, < TCvnl.ution from Ihe initial | forms of life, to in HIV in <"• Hide's billions of events, each one ' with a vanishingly small prob- j ability. The course of evolu- tion is the result of many highly improbable events and it is essentially not repeat- able, Among the many mil- lions of species which have come to existence in the past or are presently living, no species has over evolved, or ( can ever evolve, twice.'In or- ganic evolution repetition is virtually impossible. This es- sential nonv^ppatfibility of ev- olutionary processes has a de- cisive bearing on the chances that human - like organism rn«y have evolved Ln other Even assuming that there are many millions, even many billions, of planets, and that a large fraction of them con- tain life, we must conclude that with all probability we are the only intelligent beings in the universe. To quote Lorcn Eiselcy, from the Uni- versity of Pennsylvania, "Lights come and go in the night sky. Men, troubled at last by the things they build, may loss in their sleep end dream bad dreams, or be awake ' whjle the meteors whisper greenly overhead But nowhere in nil sp-ace or on a thousand worlds will there be men to share our loneli* ness ... In the nature of Irte and in the principles of evolu- tion we have had our answer. Of men elsewhere, and he- yond, there will he none for- ever."
